The objective of this one year manuscript-writing project is to analyze critically the ways in which culture, history, and biology shape a traditional supernatural assault, leading, in one specific context, to sudden nocturnal death. The term "night-mare," with a hyphen, is used in its original denotation as the nocturnal visit of an evil being that threatens to press the very life out of its terrified victim. (This form of the term is distinct from the common contemporary usage of "nightmare" to indicate a more general anxiety dream.) The nightmare "has the odd distinction of possibly being the commonest 'unknown' experience for people in industrialized societies." The proposed scholarly, book-length manuscript has five specific aims: (1) to contextualize the stable, universal night-mare phenomenon through a richly detailed overview and ethnographic analysis of first-person accounts in historical and cultural context; (2) to provide a biomedical perspective on traditional night-mare symptomatology through the examination of recent findings in laboratory sleep research; (3) to describe and assess the contribution of research breakthroughs on the nocebo phenomenon (which update and replace the notion of "voodoo death"); (4) to analyze a rare case (from my own fieldwork) of an extreme form of nocebo effect--the night-mare as a trigger for Hmong sudden nocturnal deaths in the context of traumatic cultural dislocation; and (5) to explore the consequences of night-mare encounters as they are now commonly experienced in the United States---devoid of traditional cultural explanatory models. The methods include: a critical review of the cultural, historical, and biomedical literature on the night-mare; the incorporation of previously collected and analyzed ethnographic interviews with night-mare sufferers and sleep researchers; and the qualitative content analysis of contemporary accounts collected from Web bulletin boards and online support groups for people who suffer from sleep paralysis. The proposed manuscript thus aims to fill a gap in the current healthcare, anthropological, and medical historical literature by collecting and analyzing the information necessary to comprehend an extremely common, but poorly understood, health-related phenomenon.